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      1 /*	$NetBSD: vis.c,v 1.60 2013/02/21 16:21:20 joerg Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1989, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. Neither the name of the University nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 /*-
     33  * Copyright (c) 1999, 2005 The NetBSD Foundation, Inc.
     34  * All rights reserved.
     35  *
     36  * Redistribution and use in source and binary forms, with or without
     37  * modification, are permitted provided that the following conditions
     38  * are met:
     39  * 1. Redistributions of source code must retain the above copyright
     40  *    notice, this list of conditions and the following disclaimer.
     41  * 2. Redistributions in binary form must reproduce the above copyright
     42  *    notice, this list of conditions and the following disclaimer in the
     43  *    documentation and/or other materials provided with the distribution.
     44  *
     45  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     46  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     47  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     48  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     49  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     50  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     51  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     52  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     53  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     54  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     55  * POSSIBILITY OF SUCH DAMAGE.
     56  */
     57 
     58 #include "config.h"
     59 
     60 #if defined(LIBC_SCCS) && !defined(lint)
     61 __RCSID("$NetBSD: vis.c,v 1.60 2013/02/21 16:21:20 joerg Exp $");
     62 #endif /* LIBC_SCCS and not lint */
     63 #ifdef __FBSDID
     64 __FBSDID("$FreeBSD$");
     65 #endif
     66 
     67 #include <sys/types.h>
     68 #include <sys/param.h>
     69 
     70 #include <stdint.h>
     71 #include <assert.h>
     72 #include <vis.h>
     73 #include <errno.h>
     74 #include <stdlib.h>
     75 #include <wchar.h>
     76 #include <wctype.h>
     77 
     78 #ifdef __weak_alias
     79 __weak_alias(strvisx,_strvisx)
     80 #endif
     81 
     82 #if !HAVE_VIS || !HAVE_SVIS
     83 #include <ctype.h>
     84 #include <limits.h>
     85 #include <stdio.h>
     86 #include <string.h>
     87 
     88 /*
     89  * The reason for going through the trouble to deal with character encodings
     90  * in vis(3), is that we use this to safe encode output of commands. This
     91  * safe encoding varies depending on the character set. For example if we
     92  * display ps output in French, we don't want to display French characters
     93  * as M-foo.
     94  */
     95 
     96 static wchar_t *do_svis(wchar_t *, wint_t, int, wint_t, const wchar_t *);
     97 
     98 #undef BELL
     99 #define BELL L'\a'
    100 
    101 #define iswoctal(c)	(((u_char)(c)) >= L'0' && ((u_char)(c)) <= L'7')
    102 #define iswwhite(c)	(c == L' ' || c == L'\t' || c == L'\n')
    103 #define iswsafe(c)	(c == L'\b' || c == BELL || c == L'\r')
    104 #define xtoa(c)		L"0123456789abcdef"[c]
    105 #define XTOA(c)		L"0123456789ABCDEF"[c]
    106 
    107 #define MAXEXTRAS	10
    108 
    109 #if !HAVE_NBTOOL_CONFIG_H
    110 #ifndef __NetBSD__
    111 /*
    112  * On NetBSD MB_LEN_MAX is currently 32 which does not fit on any integer
    113  * integral type and it is probably wrong, since currently the maximum
    114  * number of bytes and character needs is 6. Until this is fixed, the
    115  * loops below are using sizeof(uint64_t) - 1 instead of MB_LEN_MAX, and
    116  * the assertion is commented out.
    117  */
    118 #ifdef __FreeBSD__
    119 /*
    120  * On FreeBSD including <sys/systm.h> for CTASSERT only works in kernel
    121  * mode.
    122  */
    123 #ifndef CTASSERT
    124 #define CTASSERT(x)             _CTASSERT(x, __LINE__)
    125 #define _CTASSERT(x, y)         __CTASSERT(x, y)
    126 #define __CTASSERT(x, y)        typedef char __assert ## y[(x) ? 1 : -1]
    127 #endif
    128 #endif /* __FreeBSD__ */
    129 /*
    130 CTASSERT(MB_LEN_MAX <= sizeof(uint64_t));
    131 */
    132 #endif /* !__NetBSD__ */
    133 #endif
    134 
    135 /*
    136  * This is do_hvis, for HTTP style (RFC 1808)
    137  */
    138 static wchar_t *
    139 do_hvis(wchar_t *dst, wint_t c, int flags, wint_t nextc, const wchar_t *extra)
    140 {
    141 	if (iswalnum(c)
    142 	    /* safe */
    143 	    || c == L'$' || c == L'-' || c == L'_' || c == L'.' || c == L'+'
    144 	    /* extra */
    145 	    || c == L'!' || c == L'*' || c == L'\'' || c == L'(' || c == L')'
    146 	    || c == L',')
    147 		dst = do_svis(dst, c, flags, nextc, extra);
    148 	else {
    149 		*dst++ = L'%';
    150 		*dst++ = xtoa(((unsigned int)c >> 4) & 0xf);
    151 		*dst++ = xtoa((unsigned int)c & 0xf);
    152 	}
    153 
    154 	return dst;
    155 }
    156 
    157 /*
    158  * This is do_mvis, for Quoted-Printable MIME (RFC 2045)
    159  * NB: No handling of long lines or CRLF.
    160  */
    161 static wchar_t *
    162 do_mvis(wchar_t *dst, wint_t c, int flags, wint_t nextc, const wchar_t *extra)
    163 {
    164 	if ((c != L'\n') &&
    165 	    /* Space at the end of the line */
    166 	    ((iswspace(c) && (nextc == L'\r' || nextc == L'\n')) ||
    167 	    /* Out of range */
    168 	    (!iswspace(c) && (c < 33 || (c > 60 && c < 62) || c > 126)) ||
    169 	    /* Specific char to be escaped */
    170 	    wcschr(L"#$@[\\]^`{|}~", c) != NULL)) {
    171 		*dst++ = L'=';
    172 		*dst++ = XTOA(((unsigned int)c >> 4) & 0xf);
    173 		*dst++ = XTOA((unsigned int)c & 0xf);
    174 	} else
    175 		dst = do_svis(dst, c, flags, nextc, extra);
    176 	return dst;
    177 }
    178 
    179 /*
    180  * Output single byte of multibyte character.
    181  */
    182 static wchar_t *
    183 do_mbyte(wchar_t *dst, wint_t c, int flags, wint_t nextc, int iswextra)
    184 {
    185 	if (flags & VIS_CSTYLE) {
    186 		switch (c) {
    187 		case L'\n':
    188 			*dst++ = L'\\'; *dst++ = L'n';
    189 			return dst;
    190 		case L'\r':
    191 			*dst++ = L'\\'; *dst++ = L'r';
    192 			return dst;
    193 		case L'\b':
    194 			*dst++ = L'\\'; *dst++ = L'b';
    195 			return dst;
    196 		case BELL:
    197 			*dst++ = L'\\'; *dst++ = L'a';
    198 			return dst;
    199 		case L'\v':
    200 			*dst++ = L'\\'; *dst++ = L'v';
    201 			return dst;
    202 		case L'\t':
    203 			*dst++ = L'\\'; *dst++ = L't';
    204 			return dst;
    205 		case L'\f':
    206 			*dst++ = L'\\'; *dst++ = L'f';
    207 			return dst;
    208 		case L' ':
    209 			*dst++ = L'\\'; *dst++ = L's';
    210 			return dst;
    211 		case L'\0':
    212 			*dst++ = L'\\'; *dst++ = L'0';
    213 			if (iswoctal(nextc)) {
    214 				*dst++ = L'0';
    215 				*dst++ = L'0';
    216 			}
    217 			return dst;
    218 		default:
    219 			if (iswgraph(c)) {
    220 				*dst++ = L'\\';
    221 				*dst++ = c;
    222 				return dst;
    223 			}
    224 		}
    225 	}
    226 	if (iswextra || ((c & 0177) == L' ') || (flags & VIS_OCTAL)) {
    227 		*dst++ = L'\\';
    228 		*dst++ = (u_char)(((u_int32_t)(u_char)c >> 6) & 03) + L'0';
    229 		*dst++ = (u_char)(((u_int32_t)(u_char)c >> 3) & 07) + L'0';
    230 		*dst++ =			     (c	      & 07) + L'0';
    231 	} else {
    232 		if ((flags & VIS_NOSLASH) == 0)
    233 			*dst++ = L'\\';
    234 
    235 		if (c & 0200) {
    236 			c &= 0177;
    237 			*dst++ = L'M';
    238 		}
    239 
    240 		if (iswcntrl(c)) {
    241 			*dst++ = L'^';
    242 			if (c == 0177)
    243 				*dst++ = L'?';
    244 			else
    245 				*dst++ = c + L'@';
    246 		} else {
    247 			*dst++ = L'-';
    248 			*dst++ = c;
    249 		}
    250 	}
    251 
    252 	return dst;
    253 }
    254 
    255 /*
    256  * This is do_vis, the central code of vis.
    257  * dst:	      Pointer to the destination buffer
    258  * c:	      Character to encode
    259  * flags:     Flags word
    260  * nextc:     The character following 'c'
    261  * extra:     Pointer to the list of extra characters to be
    262  *	      backslash-protected.
    263  */
    264 static wchar_t *
    265 do_svis(wchar_t *dst, wint_t c, int flags, wint_t nextc, const wchar_t *extra)
    266 {
    267 	int iswextra, i, shft;
    268 	uint64_t bmsk, wmsk;
    269 
    270 	iswextra = wcschr(extra, c) != NULL;
    271 	if (!iswextra && (iswgraph(c) || iswwhite(c) ||
    272 	    ((flags & VIS_SAFE) && iswsafe(c)))) {
    273 		*dst++ = c;
    274 		return dst;
    275 	}
    276 
    277 	/* See comment in istrsenvisx() output loop, below. */
    278 	wmsk = 0;
    279 	for (i = sizeof(wmsk) - 1; i >= 0; i--) {
    280 		shft = i * NBBY;
    281 		bmsk = (uint64_t)0xffLL << shft;
    282 		wmsk |= bmsk;
    283 		if ((c & wmsk) || i == 0)
    284 			dst = do_mbyte(dst, (wint_t)(
    285 			    (uint64_t)(c & bmsk) >> shft),
    286 			    flags, nextc, iswextra);
    287 	}
    288 
    289 	return dst;
    290 }
    291 
    292 typedef wchar_t *(*visfun_t)(wchar_t *, wint_t, int, wint_t, const wchar_t *);
    293 
    294 /*
    295  * Return the appropriate encoding function depending on the flags given.
    296  */
    297 static visfun_t
    298 getvisfun(int flags)
    299 {
    300 	if (flags & VIS_HTTPSTYLE)
    301 		return do_hvis;
    302 	if (flags & VIS_MIMESTYLE)
    303 		return do_mvis;
    304 	return do_svis;
    305 }
    306 
    307 /*
    308  * Expand list of extra characters to not visually encode.
    309  */
    310 static wchar_t *
    311 makeextralist(int flags, const char *src)
    312 {
    313 	wchar_t *dst, *d;
    314 	size_t len;
    315 
    316 	len = strlen(src);
    317 	if ((dst = calloc(len + MAXEXTRAS, sizeof(*dst))) == NULL)
    318 		return NULL;
    319 
    320 	if (mbstowcs(dst, src, len) == (size_t)-1) {
    321 		size_t i;
    322 		for (i = 0; i < len; i++)
    323 			dst[i] = (wint_t)(u_char)src[i];
    324 		d = dst + len;
    325 	} else
    326 		d = dst + wcslen(dst);
    327 
    328 	if (flags & VIS_GLOB) {
    329 		*d++ = L'*';
    330 		*d++ = L'?';
    331 		*d++ = L'[';
    332 		*d++ = L'#';
    333 	}
    334 
    335 	if (flags & VIS_SP) *d++ = L' ';
    336 	if (flags & VIS_TAB) *d++ = L'\t';
    337 	if (flags & VIS_NL) *d++ = L'\n';
    338 	if ((flags & VIS_NOSLASH) == 0) *d++ = L'\\';
    339 	*d = L'\0';
    340 
    341 	return dst;
    342 }
    343 
    344 /*
    345  * istrsenvisx()
    346  * 	The main internal function.
    347  *	All user-visible functions call this one.
    348  */
    349 static int
    350 istrsenvisx(char *mbdst, size_t *dlen, const char *mbsrc, size_t mblength,
    351     int flags, const char *mbextra, int *cerr_ptr)
    352 {
    353 	wchar_t *dst, *src, *pdst, *psrc, *start, *extra;
    354 	size_t len, olen;
    355 	uint64_t bmsk, wmsk;
    356 	wint_t c;
    357 	visfun_t f;
    358 	int clen = 0, cerr = 0, error = -1, i, shft;
    359 	ssize_t mbslength, maxolen;
    360 
    361 	_DIAGASSERT(mbdst != NULL);
    362 	_DIAGASSERT(mbsrc != NULL);
    363 	_DIAGASSERT(mbextra != NULL);
    364 
    365 	/*
    366 	 * Input (mbsrc) is a char string considered to be multibyte
    367 	 * characters.  The input loop will read this string pulling
    368 	 * one character, possibly multiple bytes, from mbsrc and
    369 	 * converting each to wchar_t in src.
    370 	 *
    371 	 * The vis conversion will be done using the wide char
    372 	 * wchar_t string.
    373 	 *
    374 	 * This will then be converted back to a multibyte string to
    375 	 * return to the caller.
    376 	 */
    377 
    378 	/* Allocate space for the wide char strings */
    379 	psrc = pdst = extra = NULL;
    380 	if (!mblength)
    381 		mblength = strlen(mbsrc);
    382 	if ((psrc = calloc(mblength + 1, sizeof(*psrc))) == NULL)
    383 		return -1;
    384 	if ((pdst = calloc((4 * mblength) + 1, sizeof(*pdst))) == NULL)
    385 		goto out;
    386 	dst = pdst;
    387 	src = psrc;
    388 
    389 	/* Use caller's multibyte conversion error flag. */
    390 	if (cerr_ptr)
    391 		cerr = *cerr_ptr;
    392 
    393 	/*
    394 	 * Input loop.
    395 	 * Handle up to mblength characters (not bytes).  We do not
    396 	 * stop at NULs because we may be processing a block of data
    397 	 * that includes NULs.
    398 	 */
    399 	mbslength = (ssize_t)mblength;
    400 	/*
    401 	 * When inputing a single character, must also read in the
    402 	 * next character for nextc, the look-ahead character.
    403 	 */
    404 	if (mbslength == 1)
    405 		mbslength++;
    406 	while (mbslength > 0) {
    407 		/* Convert one multibyte character to wchar_t. */
    408 		if (!cerr)
    409 			clen = mbtowc(src, mbsrc, MB_LEN_MAX);
    410 		if (cerr || clen < 0) {
    411 			/* Conversion error, process as a byte instead. */
    412 			*src = (wint_t)(u_char)*mbsrc;
    413 			clen = 1;
    414 			cerr = 1;
    415 		}
    416 		if (clen == 0)
    417 			/*
    418 			 * NUL in input gives 0 return value. process
    419 			 * as single NUL byte and keep going.
    420 			 */
    421 			clen = 1;
    422 		/* Advance buffer character pointer. */
    423 		src++;
    424 		/* Advance input pointer by number of bytes read. */
    425 		mbsrc += clen;
    426 		/* Decrement input byte count. */
    427 		mbslength -= clen;
    428 	}
    429 	len = src - psrc;
    430 	src = psrc;
    431 	/*
    432 	 * In the single character input case, we will have actually
    433 	 * processed two characters, c and nextc.  Reset len back to
    434 	 * just a single character.
    435 	 */
    436 	if (mblength < len)
    437 		len = mblength;
    438 
    439 	/* Convert extra argument to list of characters for this mode. */
    440 	extra = makeextralist(flags, mbextra);
    441 	if (!extra) {
    442 		if (dlen && *dlen == 0) {
    443 			errno = ENOSPC;
    444 			goto out;
    445 		}
    446 		*mbdst = '\0';		/* can't create extra, return "" */
    447 		error = 0;
    448 		goto out;
    449 	}
    450 
    451 	/* Look up which processing function to call. */
    452 	f = getvisfun(flags);
    453 
    454 	/*
    455 	 * Main processing loop.
    456 	 * Call do_Xvis processing function one character at a time
    457 	 * with next character available for look-ahead.
    458 	 */
    459 	for (start = dst; len > 0; len--) {
    460 		c = *src++;
    461 		dst = (*f)(dst, c, flags, len >= 1 ? *src : L'\0', extra);
    462 		if (dst == NULL) {
    463 			errno = ENOSPC;
    464 			goto out;
    465 		}
    466 	}
    467 
    468 	/* Terminate the string in the buffer. */
    469 	*dst = L'\0';
    470 
    471 	/*
    472 	 * Output loop.
    473 	 * Convert wchar_t string back to multibyte output string.
    474 	 * If we have hit a multi-byte conversion error on input,
    475 	 * output byte-by-byte here.  Else use wctomb().
    476 	 */
    477 	len = wcslen(start);
    478 	maxolen = dlen ? *dlen : (wcslen(start) * MB_LEN_MAX + 1);
    479 	olen = 0;
    480 	for (dst = start; len > 0; len--) {
    481 		if (!cerr)
    482 			clen = wctomb(mbdst, *dst);
    483 		if (cerr || clen < 0) {
    484 			/*
    485 			 * Conversion error, process as a byte(s) instead.
    486 			 * Examine each byte and higher-order bytes for
    487 			 * data.  E.g.,
    488 			 *	0x000000000000a264 -> a2 64
    489 			 *	0x000000001f00a264 -> 1f 00 a2 64
    490 			 */
    491 			clen = 0;
    492 			wmsk = 0;
    493 			for (i = sizeof(wmsk) - 1; i >= 0; i--) {
    494 				shft = i * NBBY;
    495 				bmsk = (uint64_t)0xffLL << shft;
    496 				wmsk |= bmsk;
    497 				if ((*dst & wmsk) || i == 0)
    498 					mbdst[clen++] = (char)(
    499 					    (uint64_t)(*dst & bmsk) >>
    500 					    shft);
    501 			}
    502 			cerr = 1;
    503 		}
    504 		/* If this character would exceed our output limit, stop. */
    505 		if (olen + clen > (size_t)maxolen)
    506 			break;
    507 		/* Advance output pointer by number of bytes written. */
    508 		mbdst += clen;
    509 		/* Advance buffer character pointer. */
    510 		dst++;
    511 		/* Incrment output character count. */
    512 		olen += clen;
    513 	}
    514 
    515 	/* Terminate the output string. */
    516 	*mbdst = '\0';
    517 
    518 	/* Pass conversion error flag out. */
    519 	if (cerr_ptr)
    520 		*cerr_ptr = cerr;
    521 
    522 	free(extra);
    523 	free(pdst);
    524 	free(psrc);
    525 
    526 	return (int)olen;
    527 out:
    528 	free(extra);
    529 	free(pdst);
    530 	free(psrc);
    531 	return error;
    532 }
    533 #endif
    534 
    535 #if !HAVE_SVIS
    536 /*
    537  *	The "svis" variants all take an "extra" arg that is a pointer
    538  *	to a NUL-terminated list of characters to be encoded, too.
    539  *	These functions are useful e. g. to encode strings in such a
    540  *	way so that they are not interpreted by a shell.
    541  */
    542 
    543 char *
    544 svis(char *mbdst, int c, int flags, int nextc, const char *mbextra)
    545 {
    546 	char cc[2];
    547 	int ret;
    548 
    549 	cc[0] = c;
    550 	cc[1] = nextc;
    551 
    552 	ret = istrsenvisx(mbdst, NULL, cc, 1, flags, mbextra, NULL);
    553 	if (ret < 0)
    554 		return NULL;
    555 	return mbdst + ret;
    556 }
    557 
    558 char *
    559 snvis(char *mbdst, size_t dlen, int c, int flags, int nextc, const char *mbextra)
    560 {
    561 	char cc[2];
    562 	int ret;
    563 
    564 	cc[0] = c;
    565 	cc[1] = nextc;
    566 
    567 	ret = istrsenvisx(mbdst, &dlen, cc, 1, flags, mbextra, NULL);
    568 	if (ret < 0)
    569 		return NULL;
    570 	return mbdst + ret;
    571 }
    572 
    573 int
    574 strsvis(char *mbdst, const char *mbsrc, int flags, const char *mbextra)
    575 {
    576 	return istrsenvisx(mbdst, NULL, mbsrc, 0, flags, mbextra, NULL);
    577 }
    578 
    579 int
    580 strsnvis(char *mbdst, size_t dlen, const char *mbsrc, int flags, const char *mbextra)
    581 {
    582 	return istrsenvisx(mbdst, &dlen, mbsrc, 0, flags, mbextra, NULL);
    583 }
    584 
    585 int
    586 strsvisx(char *mbdst, const char *mbsrc, size_t len, int flags, const char *mbextra)
    587 {
    588 	return istrsenvisx(mbdst, NULL, mbsrc, len, flags, mbextra, NULL);
    589 }
    590 
    591 int
    592 strsnvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags,
    593     const char *mbextra)
    594 {
    595 	return istrsenvisx(mbdst, &dlen, mbsrc, len, flags, mbextra, NULL);
    596 }
    597 
    598 int
    599 strsenvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags,
    600     const char *mbextra, int *cerr_ptr)
    601 {
    602 	return istrsenvisx(mbdst, &dlen, mbsrc, len, flags, mbextra, cerr_ptr);
    603 }
    604 #endif
    605 
    606 #if !HAVE_VIS
    607 /*
    608  * vis - visually encode characters
    609  */
    610 char *
    611 vis(char *mbdst, int c, int flags, int nextc)
    612 {
    613 	char cc[2];
    614 	int ret;
    615 
    616 	cc[0] = c;
    617 	cc[1] = nextc;
    618 
    619 	ret = istrsenvisx(mbdst, NULL, cc, 1, flags, "", NULL);
    620 	if (ret < 0)
    621 		return NULL;
    622 	return mbdst + ret;
    623 }
    624 
    625 char *
    626 nvis(char *mbdst, size_t dlen, int c, int flags, int nextc)
    627 {
    628 	char cc[2];
    629 	int ret;
    630 
    631 	cc[0] = c;
    632 	cc[1] = nextc;
    633 
    634 	ret = istrsenvisx(mbdst, &dlen, cc, 1, flags, "", NULL);
    635 	if (ret < 0)
    636 		return NULL;
    637 	return mbdst + ret;
    638 }
    639 
    640 /*
    641  * strvis - visually encode characters from src into dst
    642  *
    643  *	Dst must be 4 times the size of src to account for possible
    644  *	expansion.  The length of dst, not including the trailing NULL,
    645  *	is returned.
    646  */
    647 
    648 int
    649 strvis(char *mbdst, const char *mbsrc, int flags)
    650 {
    651 	return istrsenvisx(mbdst, NULL, mbsrc, 0, flags, "", NULL);
    652 }
    653 
    654 int
    655 strnvis(char *mbdst, size_t dlen, const char *mbsrc, int flags)
    656 {
    657 	return istrsenvisx(mbdst, &dlen, mbsrc, 0, flags, "", NULL);
    658 }
    659 
    660 /*
    661  * strvisx - visually encode characters from src into dst
    662  *
    663  *	Dst must be 4 times the size of src to account for possible
    664  *	expansion.  The length of dst, not including the trailing NULL,
    665  *	is returned.
    666  *
    667  *	Strvisx encodes exactly len characters from src into dst.
    668  *	This is useful for encoding a block of data.
    669  */
    670 
    671 int
    672 strvisx(char *mbdst, const char *mbsrc, size_t len, int flags)
    673 {
    674 	return istrsenvisx(mbdst, NULL, mbsrc, len, flags, "", NULL);
    675 }
    676 
    677 int
    678 strnvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags)
    679 {
    680 	return istrsenvisx(mbdst, &dlen, mbsrc, len, flags, "", NULL);
    681 }
    682 
    683 int
    684 strenvisx(char *mbdst, size_t dlen, const char *mbsrc, size_t len, int flags,
    685     int *cerr_ptr)
    686 {
    687 	return istrsenvisx(mbdst, &dlen, mbsrc, len, flags, "", cerr_ptr);
    688 }
    689 #endif
    690